Art of treating oils



Patented Sept. 7, 1926.

UNITED STATES GEORGE KOLSKY, OF JERSEY CITY, NEW JERSEY.

ART OF TREATING OILS.

No Drawing.

The present invention relates to the art of treating oils.

More particularly the invention relates to the treatment of hydro-carbonoils for the purpose of converting relatively high boiling point oils tolower boiling point saturated oils of high quality.

Various processes have been proposed for the conversion of relativelyhigh boilingpoint h dro-carbon oils to lower boiling point oi s, whichare subject to various disadvantages from a commercial viewpoint. One ofthe well-known prior processes is that known as cracking, in which thehydrocarbon oils to be treated are subjected to the application of heatand pressure usually at temperatures within the limits of about 750 to860 degrees Fahrenheit. In such processes only about 20 to per cent ofan average raw stock can be converted into gasoline, and considerablequantities of low grade residues, coke and permanent gases are formed,the cheapest raw materials, such as heavy crudes and residues from heavyCalifornia, Gulf and Mexican oils cannot be used commercially for theproduction of gasoline in these processes because of the excessivedeposition of carbon and low yield of gasoline obtained. Gasolineproduced by the cracking processes comprises to a large extentunsaturated hydrocarbons, or hydrocarbons which do not contain enoughhydrogen to satisfy all of the chemical combining power of the carboncontained therein. As is well known unsaturated hydrocarbons areundesirable and etroleum roducts containing them are of ower gra e andvalue than those which are composed substantially of.

saturated hydrocarbons.

\ It has been found impossible to attain complete conversion of highboiling point hydrocarbons to low boiling point hydrocarbons by crackingor any of the other prior processes. Commercial gasoline contains on anaverage of 84 to 85 per cent of carbon, and 15 to 16 per cent ofhydrogen while the composition of the raw materials varies according tolocality from which it is secured. .A parafline base Pennsylvania crudeoil has 86 per cent carbon and 14 per cent hydrogen; a Mexican crude has84 per cent carbon and only 10 per cent hydrogen and there is a greatervariation than this in the composition of the various refiner residuesand intermediates. It is accordingly evident that for a completeconversion, the dissociation Application filed November 27,*1925. SerialNo. 71,805.

catalyzers must be renewed frequently, and

their catalytic activity is rapidly paralyzed by the impurities such assulphides of carbon or hydrogen or other sulphur compounds contained inthe raw material and continuously present during the treatment. 2

Other well known processes for the production of lower boiling pointhydrocarbons or gasoline from the higher boiling point hydrocarbons arethose in which the oils to be treated are heated in the presence .of acatalytic substance such, for example, as anhydrous aluminum chloride attemperatures below 600 degrees Fahrenheit. Saturated low boiling pointhydrocarbons of high quality are produced but these processes aresubject to the difliculty that the aluminum chloride or other catalyticagents utilized are expensive, their catalytic activity disappears afterabout thirty or forty hours of operation, and they become converted intocoky mass and are regenerated or recovered only with great difiiculty. Afurther disadvantage of these processes is that in order to provide thenecessary hydrogen to produce saturated hydrocarbons, a certain portionof the hydrocarbon is robbed of its hydrogen content. As high as 15 percent of the raw stuff treated may be reduced to coke due to the robbingof the hydrogen content and to the decomposition which proceeds duringthe process.

,It has also been proposed to efiect hydrogenation in combination withthe dissociation of the hydrocarbons in the presence of catalyzers, andat temperatures below the usual cracking temperatures, by utilizing hydrogen generated by reacting hydrochloric acid with metal. This processis inoperative for the reason that reaction of the hydrochloric acidwith the metal forms molecular hydrogen which does not readily combinewith the unsaturated hydrocarbons. The presence of free hydrochloricacid in the usual treating processes and metallic apparatus is moreo erh ghly undesirable for the reason that reaction vessels are attacked andcorroded by the free acid.

Efforts have been made to hydrogenate hydrocarbon oils with hydrogenmade from steam and metals or carbon at very high temperatures andpressures. Thishas been unsuccessful commercially for the reason thatthe required temperatures and pressures are so great that the crackingreactions are uncontrollable and cannot be coordinated with theformation of the hydrogen, and the extreme temperatures destroy theproducts. In other processes using free hydrogen pressures as high as100 atmospheres or more are required; the plants that are constructed tooperate at these high pressures are very expensive in first costand inmaintenance, the addition of the hydrogen is too expensive and difiicultby this method and has been entirely impractical from a commercial viewpoint.

I have discovered that it is possible to synchronize the dissociation ofthe higher boiling point hydrocarbons and the formation of nascenthydrogen at temperatures and pressures within the limits at presentutilized in the well known cracking processes; and also within thetemperaturelimits at which the present well known catalytic reactions inthe presence of aluminum chloride and like compounds is carried out. Inthis way the hydrogen necessary to saturate the hydrocarbons is suppliedin nascent or atomic form at the temperature and pressures at whichdissociation or the formation of hydrocarbon remnants occurs and animmediate combination of the nascent hydrogen with the dissociatedcompounds or hydrocarbon remnants is effected before a substantialproportion of the hydrocarbons can break up into free gases and carbons.A considerably improved yield and quality of lower boiling point oils isin this wa attained and I have found that the cheaper grades of rawmaterials which at present are commercially unavailable gfor crackingmay be profitably converted into gasoline by means of my improvedprocess. Heavy crudes and residues from heavy California, Gulf andMexican oils may be treated successfully in accordance with myinvention, and high yield high grade low boiling point saturatedhydrocarbons of saturated nature, free from undesirable olefines areproduced.

Accordingly objects of my invention are to provide novel improved, andmore economical processes for bons; to provide novel processes forincreasing the yield of lower boiling point hydrocarbons from higherboiling point hydrocarbone; and to provide novel processes of bydrogenating, and dissociating hydrocarbon materials. v

Further objects of the invention are such treating hydrocaras may beattained by a utilization of the various novel combinations,subcombinations, steps and principles hereinafter set forth for thevarious uses and in the various relation to which they are applicable bythose skilled in the art, and as defined by the terms of the appendedclaims.

In accordance with my invention, the dissociation of the higher boilingpoint hydrocarbons such as is effected in the various well knowncracking processes, may be carried out simultaneously with the formationor generation of hydrogen in a nascent state and in such manner that thehydrogen acts on the hydrocarbon molecule at the point of cracking,combining with and saturating the lower boiling point unsaturatedhydrocarbons before a further dissociation or decomposition with aresulting deposition of carbon and formation of fixed gases can occur.This is preferably effected by carrying out the reactions for theformation of nascent hydrogen in a manner to cause the simultaneousformation of substances which aid the dissociation of the hydrocarbons,and simultaneous hydrogenation of'the components thereof by catalyticaction. In this way the cracking, catalysis, hydrogenation andgeneration of nascent hydrogen are synchronized, resulting in decreasedformation of free carbon and fixed gases, and an increased yield insaturated low boiling point hydrocarbons. \Vhile it is preferred toutilize the cracking reactions, it will be understood that this is notessential and that the formation of nascent hydrogen and a catalyzingsubstance together with hydrogenation may be carried out below thecracking temperatures and pressures with decidedly improved results overthose attained in the aluminum chloride and like prior catalyticprocesses.

In the preferred methods of carrying out my invention I react ammoniumsalts of the haloid group such as chloride with finely divided iron,Zinc, copper, aluminum or similar metals, or finely divided metallicalloys or mixtures of metals to produce metallic salts or chlorides,free ammonia as, and nascent hydrogen, in the presence of thehydrocarbons to be treated. The metallic chlorides act as catalyticagents in well known manner. The ammonia gas which is evolved is inertto the hydrocarbons at the temperatures utilized. When finely dividediron is used with the ammonium chloride, their reaction starts below 300degrees F.; is slow up to about 400 degrees F is active above about 400degrees F.; and is completed between about 650 and 750 degrees If. inaccordance with the pressure in the apparatus. At very high pressures itmay not be completed until a temperature of 800 degrees F. or more isreached. When finely divided z nc 9 alum i ut li ed ith ammoni- .larvariable factors.

um chloride the, temperatures at which the reactions occur are slightlylower, 'while when finely divided copper is utilized lthe temperaturesare slightly higher than when iron is utilized. Although ammonium chlo--ride-is preferably utilized, in general anyammonium 'salt of the haloidgroup such for example asbromides, and the like may be used effectivelywith finely divided metals to generate the nascent hydrogen in my improved processes. I

While the range of temperatures at which; the reactions have beenobservedto occur in casewhen finely divided iron is used have beengiven, it will be understood that the reactions with other metals arenot limited to these temperature ranges. The best condition for anyparticular oil to be treated may be determined experimentally and willbe dependent upon the composition of the raw product, the time oftreatment, the metal used, the pressure utilized and simi- For example,using ammonium chloride and the proper metals, a Pennsylvania crude oilmay be hydrogenated and completely treated at the temperatures justabove its boiling point. Relatively heavy oils such as heavy Californiaand Mexican crudes require higher temperatures and pressures and alonger time of treatment for complete hydrogenation and dissociation ina commercially satisfactory manner. The reactions are carried out in amanner dependent upon the desired degree of conversion or result and theraw material treated, and the temperatures, pressures, and duration oftreatment are varied accordingly. i Certain other of the ammonium saltsor compounds such as sulphates, carbonates, sulphites and the like mayalso be utilized in carrying out my improved processes, providing thatsuch 'metals are reacted therewith as will eliminate the influence ofwater, or will react with water as rapidly asit is formed to generatenascent hydrogen. For example neither aluminum nor iron may be utilizedwith such ammonium compounds,

' as the temperatures at which they will re act with water to formnascent hydrogen are entirely too'high for the purposes of my invention.Zinc dust, however, maybe utilized with such compounds, and a mixture ofammonium sulphate or carbonate with zinc dust will produce the desiredresult, The substances must be so chosen that they will liberate nascenthydrogen within the desired temperature limits and at the same time willnot cause undersirable reactions such as the formation of free acids totake place simultaneously. I As the reactions do not proceed, at ordinary temperatures, nor in the presence of water, it is assumed that themetal having a high afiinity for the radical or group com- In thepreferred manner bined with the chemical group NH within the temperaturelimits set forth, combines with the radicalor group leaving the chemi--cal group NH which immediately splits up into NH, and atomic or nascenthydrogen. The' processes are accordingly carried out in the presence offree excess ammonium vapors which are evolved continuously, and incracking operations the cracking occurs in an atmosphere of ammoniaunder pressure.- Under these conditions when the process is properlycarried out, the existence of free vacid is prevented.

of practicing the invention, ammonium chloride and finally divided ironare utilized. Under ordinary conditions of heating, ammonium chloridedissociates intoammonia and hydrochloric acid vapor. In my improvedprocess the formation of hydrochloric acid vapors is prevented by thecombination of the'chlorine with the finely divided metal, and thepres-v ence of free acid is entirely avoided. This permits the carryingout o my invention in apparatus made of steel'or suitable steel alloywithout undue corrosion.

When the reactions are carried out at cracking temperatures andpressures in the presence of hydrocarbons to be treated, the evolvedammonia gases may be regulatedto control the pressure in the treatingapparatus, and the benefit of the reactions may be attained over a widerange of temperatures. By permitting higher pressures to develop in theapparatus, the reactions may be caused to proceed at highertemperatures, and the speed of reaction between the ammonium compoundand the metal or metallic alloy or mixture may be controlled by varyingthe pressure in the vessel In this way the generation of the nascenthydrogen, and the dissociation of the hydrocarbons for different gradesof oil to be treated may be controlled to give the maximum efficiency ofoperation.

In the preferred embodiment of the invention the substances enteringinto the reaction for the formation of the nascent hydrogen and thecatalytic substances are preferably regenerated or recovered for use insucceeding operations. The regeneration is preferably carried out sothat a complete cycle of operations is maintained.

By way of a specific example of carrying out the invention, thereactions will be given for the case in which ammonium chloride andfinely divided iron are utilized and in which regeneration ofthesubstances is carried out in a cycle. The ammonium chloride andfinelydivided iron react at the temperatures utilized to produce ironchloride, free ammonia, and nascent hydrogen as set forth in thefollowing equation:

1 2NH.o1+F e=Feo1 N ,+2H. The raw oil to be treated is mixed with asuitable quantity of dry ammonium chloride and finely divided iron orother metal and the mixture is heated and treated preferably as is donein the usual cracking or catalytic processes and in any usual type ofapparatus. The quantities necessary for complete treatment of a givenproduct may be readily determined from equation (1), and from the amountof hydrogen necessary to effect hydrogenation and saturation of theparticular grade of hydrocarbon to be.

treated. For example if the'raw material to be, treated requires twoparts of hydrogen per 100 parts of raw oil to conform to the hydrogencontent of gasoline, the quantities for complete hydrogenation should beat least one molecule, or 55 parts of iron, and

'2 molecules or 106 parts of ammonium chlo- (2)2NH,Cl|-Fe-(-unsaturated.

V, hydrocarbon: FeCh-I-QNI-L-I-saturated hydrocarbon.

For example, if the raw material has been broken down through crackingand dissociating reactions to amylen-e the reactions will be as follows:

The gasoline vapor and other low boiling point hydrocarbon vaporstogether with the ammonia vapors formed during the reactions arereleased from the still or the reaction vessel preferably as fast asthey are formed and preferably in continuous manner. 7 The release ofthe evolved vapors may be controlled to maintain predetermined pressuresin the reaction Vessel and to control the reaction temperatures incracking operations'if desired. The gasoline vapors are condensed in anysuitable manner and separated from the ammonia vapors. The ammoniavapors are then preferably brought in contact in the presence of waterwith the iron chloride formed in the reaction vessel and ammoniumchloride is recovered for use in va following operation. hydroxideformed in the regeneration of the ammonium chloride is preferablyreduced to metallic ,iron and also used over in a suc- .ceedingoperation. The reduction of the iron hydroxide maybe effected withreducing gases available at a refinery such as still gases, or withhydrogen, or with industrial gas such. as water gas. In the preferredinstead of one. of ammonium chloride with finely divided The iron methodof regeneration, iron chloride from the reaction vessel is preferablyseparated from the adhering oil by heating the same, and the vapors fromthe adhering residual oil-are utilized for the reduction of the ironhydroxide from a previous operation.

The regeneration reactions may be expressed in the following equations:

(4) FeCl +2NH +2H Q= I Fe (OH) +2NH,C1. (5) Fe(OH) +R-educing gases:

H O+CO+Fe The treatment of the hydrocarbons and regeneration of thereacting substances may in this manner be carried out in a cycle ofoperations, and in economical manner. Finely divided metal from anysource may be used, but it is preferable to utilize the metal which hasbeen recovered from a regeneration of the metallic salts formed in thetreatment of the hydrocarbons as the restood that the process is notlimited to these quantities. Improved results and yields as compared toordinary methods of treating high boiling point oils to produce lowboiling point oils may be obtained even though much smaller quantitiesare used than will be necessary to effect complete hydrogenation of thero'duct.

It w1ll be found that desirable results may be attained by a mixture ofammonium compounds of the character mentioned with a finely dividedmixture of two or more metals In certain cases a mixture iron and asmall quantity of metallic aluminum gives excellent results due to theadditional catalytic action of the aluminum chloride formed. Thequantity of iron and ammonium chloride may be calculated and used inanamount to give the desired hydrogenation while the quantity of aluminumused, preferably in catalytically active form may be so small as to benegligible for purposes of regeneration.

If a mixture of anhydrous ammonium chloride and finely divided aluminumis used in place 'of the aluminum chloride in the well known catalyticprocesses, and the treatment of the oils is then carried out in themanner commonly used in such processes, all of the desirable results ofthese aluminum chloride processes will be assured, and in addition amuch better yield of saturated prod.

uct will be obtained, for the reason that the hydrocarbon remnants arehydrogenated and saturated and the decomposition and formation of cokewith all its disadvantages is reduced to a minimum or entirely avoided.It will also be found that in a cyclic operation the ammonium chlorideand the metallic aluminum can be more easily and more ecowill react toevolve hydrogen and free ammonia.

2. In a process of treating hydrocarbon oils, the step of heating thesame in the presence of an ammonium salt of the intermediate members ofthe halogen group and finely divided metal.

3. In a process of treating hydrocarbon oils, the step of heating thesame in the resence of ammonium chloride and finely ivi'ded iron.

4. The process of treating hydrocarbon 011s which comprises reacting theoils with a monia at temperatures substantially at or a above the,boiling point of said oils to efiect simultaneously the cracking of thehighboiling point hydrocarbons and the hydrogenation of the unsaturatedproducts formed during said cracking.

5. The process for treating oils which comprises reacting the same withammonium chloride and a metal at temperatures substantially at or abovethe boiling point of said oils to simultaneously produce a catalyticmetallic salt, crack the oils and hydrogenate the unsaturatedhydrocarbon products.

6. The process of treating hydrocarbon oils which comprises reacting thehydrocarbons with an ammonium salt in the presence of finely divided.metal that will react to evolve hydrogen and free ammonia at atemperature between 300 and 800 drawing the low boiling pointhydrocarbons thus formed, and controlling the pressure of the evolvedvapors to controlthe activity of reaction.

In testimony whereof I afiix my signature.

GEORGE 'KoLsKY.

F., withr j

